Geology of select stone : I sculpt stones that have fascinating geologic histories
British Columbia Granitic Conglomerate
This generally gray, black and white conglomerate is a called polymictic because of the wide variety of rock types it contains. It was originally deposited in a fast flowing stream along an ancient mountain range in central British Columbia during the lower Cretaceous period. During the Pleistocene Ice Ages, glaciers picked up, dragged south and dropped off this durable stone. It can be found as surface glacial “erratics” throughout the North Puget Sound region, including on our very own Orcas Island.
Orbicular Granite
Orbicular granite is a rare igneous rock distinguished by rounded structures called orbicules, which contain concentric layers of contrasting minerals. These orbicules typically formed around a mineral grain or rock fragment while the surrounding magma was cooling and crystallizing. The exact conditions required for their formation remain debated, but they appear to involve unusual fluctuations in temperature, chemistry, and crystal growth. When cut and polished, orbicular granite reveals striking natural patterns that resemble eyes, planets, or ripples frozen in stone.
Hecata Polymictic Conglomerate
Polymictic conglomerates contain many different rock types which are welded together to form an integrated amalgamation of stones. This polymictic is from SE Alaska and records a high-energy streambed flowing from an ancient mountain range. Dazzling in colors and mesmerizing in complexity. With stones such as these, I keep my designs simple.
Twin Sisters Dunite
Dunite is a very unusual upper mantle, metamorphic rock which rose from over 10 miles below the Earth's surface to be emplaced in the northern Cascade Mountains over 70 million years ago. Twin Sisters mountains of NW Washington State are made entirely of Dunite and represent the largest single outcrop of this stone in the world. It is almost entirely made from the ferro-magnesium mineral Olivine. It is a very heavy stone which when polished produces a beautiful light to dark green, modeled fabric reminiscent to storm clouds drifting over a modern skyscraper.